The photostream is a chronological arrangement with the newest on the top and the old material endlessly sinking down into back pages.
The "description box" is where you put the text. It's essentially your post: You can write anything you want here -- it doesn't have to be a description of the photograph.
There is a place for comments on each photo, which can be used for comments on the post as well as for the photograph.
Blogs could be improved by adding some of the Flickr-style functions: Why not have a button to click to rearrange the posts, so that they are not in chronological order anymore but grouped by tags or by most viewed, most comments, most "favorited," and most interesting?
Personally, I'm fascinated by the Flickr concept of "interestingness":
There are lots of things that make a photo 'interesting' (or not) in the Flickr. Where the clickthroughs are coming from; who comments on it and when; who marks it as a favorite; its tags and many more things which are constantly changing. Interestingness changes over time, as more and more fantastic photos and stories are added to Flickr.Why isn't there something like this working to find things in blogs? We're still using the relatively crude selection method of counting links.
On Flickr, you can reorder your own
UPDATE: On Flickr, you can't rank the photos of another individual, only your own. I suppose there is some privacy interest in that.
ANOTHER UPDATE: It was my son John who informed me that you can't get to other people's "most interesting" pages. He added that you could make a Flickr set out of your "most interesting" pages, and then he did that with his: here.